sysctl: add proc_do_large_bitmap
[safe/jmp/linux-2.6] / kernel / trace / trace_kprobe.c
index 7ac728d..1251e36 100644 (file)
@@ -635,12 +635,12 @@ static int create_trace_probe(int argc, char **argv)
                        event = strchr(group, '/') + 1;
                        event[-1] = '\0';
                        if (strlen(group) == 0) {
-                               pr_info("Group name is not specifiled\n");
+                               pr_info("Group name is not specified\n");
                                return -EINVAL;
                        }
                }
                if (strlen(event) == 0) {
-                       pr_info("Event name is not specifiled\n");
+                       pr_info("Event name is not specified\n");
                        return -EINVAL;
                }
        }
@@ -673,7 +673,7 @@ static int create_trace_probe(int argc, char **argv)
                        return -EINVAL;
                }
                /* an address specified */
-               ret = strict_strtoul(&argv[0][2], 0, (unsigned long *)&addr);
+               ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr);
                if (ret) {
                        pr_info("Failed to parse address.\n");
                        return ret;
@@ -942,7 +942,7 @@ static const struct file_operations kprobe_profile_ops = {
 };
 
 /* Kprobe handler */
-static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
+static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
 {
        struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
        struct kprobe_trace_entry *entry;
@@ -962,7 +962,7 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
        event = trace_current_buffer_lock_reserve(&buffer, call->id, size,
                                                  irq_flags, pc);
        if (!event)
-               return 0;
+               return;
 
        entry = ring_buffer_event_data(event);
        entry->nargs = tp->nr_args;
@@ -972,11 +972,10 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
 
        if (!filter_current_check_discard(buffer, call, entry, event))
                trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
-       return 0;
 }
 
 /* Kretprobe handler */
-static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri,
+static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
                                          struct pt_regs *regs)
 {
        struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
@@ -995,7 +994,7 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri,
        event = trace_current_buffer_lock_reserve(&buffer, call->id, size,
                                                  irq_flags, pc);
        if (!event)
-               return 0;
+               return;
 
        entry = ring_buffer_event_data(event);
        entry->nargs = tp->nr_args;
@@ -1006,8 +1005,6 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri,
 
        if (!filter_current_check_discard(buffer, call, entry, event))
                trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
-
-       return 0;
 }
 
 /* Event entry printers */
@@ -1158,216 +1155,127 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
        return 0;
 }
 
-static int __probe_event_show_format(struct trace_seq *s,
-                                    struct trace_probe *tp, const char *fmt,
-                                    const char *arg)
+static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
 {
        int i;
+       int pos = 0;
 
-       /* Show format */
-       if (!trace_seq_printf(s, "\nprint fmt: \"%s", fmt))
-               return 0;
+       const char *fmt, *arg;
 
-       for (i = 0; i < tp->nr_args; i++)
-               if (!trace_seq_printf(s, " %s=%%lx", tp->args[i].name))
-                       return 0;
+       if (!probe_is_return(tp)) {
+               fmt = "(%lx)";
+               arg = "REC->" FIELD_STRING_IP;
+       } else {
+               fmt = "(%lx <- %lx)";
+               arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
+       }
 
-       if (!trace_seq_printf(s, "\", %s", arg))
-               return 0;
+       /* When len=0, we just calculate the needed length */
+#define LEN_OR_ZERO (len ? len - pos : 0)
 
-       for (i = 0; i < tp->nr_args; i++)
-               if (!trace_seq_printf(s, ", REC->%s", tp->args[i].name))
-                       return 0;
+       pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
 
-       return trace_seq_puts(s, "\n");
-}
+       for (i = 0; i < tp->nr_args; i++) {
+               pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%%lx",
+                               tp->args[i].name);
+       }
 
-#undef SHOW_FIELD
-#define SHOW_FIELD(type, item, name)                                   \
-       do {                                                            \
-               ret = trace_seq_printf(s, "\tfield:" #type " %s;\t"     \
-                               "offset:%u;\tsize:%u;\tsigned:%d;\n", name,\
-                               (unsigned int)offsetof(typeof(field), item),\
-                               (unsigned int)sizeof(type),             \
-                               is_signed_type(type));                  \
-               if (!ret)                                               \
-                       return 0;                                       \
-       } while (0)
+       pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
 
-static int kprobe_event_show_format(struct ftrace_event_call *call,
-                                   struct trace_seq *s)
-{
-       struct kprobe_trace_entry field __attribute__((unused));
-       int ret, i;
-       struct trace_probe *tp = (struct trace_probe *)call->data;
+       for (i = 0; i < tp->nr_args; i++) {
+               pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
+                               tp->args[i].name);
+       }
 
-       SHOW_FIELD(unsigned long, ip, FIELD_STRING_IP);
-       SHOW_FIELD(int, nargs, FIELD_STRING_NARGS);
+#undef LEN_OR_ZERO
 
-       /* Show fields */
-       for (i = 0; i < tp->nr_args; i++)
-               SHOW_FIELD(unsigned long, args[i], tp->args[i].name);
-       trace_seq_puts(s, "\n");
-
-       return __probe_event_show_format(s, tp, "(%lx)",
-                                        "REC->" FIELD_STRING_IP);
+       /* return the length of print_fmt */
+       return pos;
 }
 
-static int kretprobe_event_show_format(struct ftrace_event_call *call,
-                                      struct trace_seq *s)
+static int set_print_fmt(struct trace_probe *tp)
 {
-       struct kretprobe_trace_entry field __attribute__((unused));
-       int ret, i;
-       struct trace_probe *tp = (struct trace_probe *)call->data;
+       int len;
+       char *print_fmt;
 
-       SHOW_FIELD(unsigned long, func, FIELD_STRING_FUNC);
-       SHOW_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP);
-       SHOW_FIELD(int, nargs, FIELD_STRING_NARGS);
+       /* First: called with 0 length to calculate the needed length */
+       len = __set_print_fmt(tp, NULL, 0);
+       print_fmt = kmalloc(len + 1, GFP_KERNEL);
+       if (!print_fmt)
+               return -ENOMEM;
 
-       /* Show fields */
-       for (i = 0; i < tp->nr_args; i++)
-               SHOW_FIELD(unsigned long, args[i], tp->args[i].name);
-       trace_seq_puts(s, "\n");
+       /* Second: actually write the @print_fmt */
+       __set_print_fmt(tp, print_fmt, len + 1);
+       tp->call.print_fmt = print_fmt;
 
-       return __probe_event_show_format(s, tp, "(%lx <- %lx)",
-                                        "REC->" FIELD_STRING_FUNC
-                                        ", REC->" FIELD_STRING_RETIP);
+       return 0;
 }
 
 #ifdef CONFIG_PERF_EVENTS
 
 /* Kprobe profile handler */
-static __kprobes int kprobe_profile_func(struct kprobe *kp,
+static __kprobes void kprobe_perf_func(struct kprobe *kp,
                                         struct pt_regs *regs)
 {
        struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
        struct ftrace_event_call *call = &tp->call;
        struct kprobe_trace_entry *entry;
-       struct trace_entry *ent;
-       int size, __size, i, pc, __cpu;
+       int size, __size, i;
        unsigned long irq_flags;
-       char *trace_buf;
-       char *raw_data;
        int rctx;
 
-       pc = preempt_count();
        __size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args);
        size = ALIGN(__size + sizeof(u32), sizeof(u64));
        size -= sizeof(u32);
-       if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+       if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
                     "profile buffer not large enough"))
-               return 0;
-
-       /*
-        * Protect the non nmi buffer
-        * This also protects the rcu read side
-        */
-       local_irq_save(irq_flags);
-
-       rctx = perf_swevent_get_recursion_context();
-       if (rctx < 0)
-               goto end_recursion;
-
-       __cpu = smp_processor_id();
-
-       if (in_nmi())
-               trace_buf = rcu_dereference(perf_trace_buf_nmi);
-       else
-               trace_buf = rcu_dereference(perf_trace_buf);
-
-       if (!trace_buf)
-               goto end;
+               return;
 
-       raw_data = per_cpu_ptr(trace_buf, __cpu);
-
-       /* Zero dead bytes from alignment to avoid buffer leak to userspace */
-       *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
-       entry = (struct kprobe_trace_entry *)raw_data;
-       ent = &entry->ent;
+       entry = perf_trace_buf_prepare(size, call->id, &rctx, &irq_flags);
+       if (!entry)
+               return;
 
-       tracing_generic_entry_update(ent, irq_flags, pc);
-       ent->type = call->id;
        entry->nargs = tp->nr_args;
        entry->ip = (unsigned long)kp->addr;
        for (i = 0; i < tp->nr_args; i++)
                entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
-       perf_tp_event(call->id, entry->ip, 1, entry, size);
 
-end:
-       perf_swevent_put_recursion_context(rctx);
-end_recursion:
-       local_irq_restore(irq_flags);
-
-       return 0;
+       perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags, regs);
 }
 
 /* Kretprobe profile handler */
-static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri,
+static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
                                            struct pt_regs *regs)
 {
        struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
        struct ftrace_event_call *call = &tp->call;
        struct kretprobe_trace_entry *entry;
-       struct trace_entry *ent;
-       int size, __size, i, pc, __cpu;
+       int size, __size, i;
        unsigned long irq_flags;
-       char *trace_buf;
-       char *raw_data;
        int rctx;
 
-       pc = preempt_count();
        __size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args);
        size = ALIGN(__size + sizeof(u32), sizeof(u64));
        size -= sizeof(u32);
-       if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+       if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
                     "profile buffer not large enough"))
-               return 0;
-
-       /*
-        * Protect the non nmi buffer
-        * This also protects the rcu read side
-        */
-       local_irq_save(irq_flags);
+               return;
 
-       rctx = perf_swevent_get_recursion_context();
-       if (rctx < 0)
-               goto end_recursion;
-
-       __cpu = smp_processor_id();
-
-       if (in_nmi())
-               trace_buf = rcu_dereference(perf_trace_buf_nmi);
-       else
-               trace_buf = rcu_dereference(perf_trace_buf);
-
-       if (!trace_buf)
-               goto end;
-
-       raw_data = per_cpu_ptr(trace_buf, __cpu);
-
-       /* Zero dead bytes from alignment to avoid buffer leak to userspace */
-       *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
-       entry = (struct kretprobe_trace_entry *)raw_data;
-       ent = &entry->ent;
+       entry = perf_trace_buf_prepare(size, call->id, &rctx, &irq_flags);
+       if (!entry)
+               return;
 
-       tracing_generic_entry_update(ent, irq_flags, pc);
-       ent->type = call->id;
        entry->nargs = tp->nr_args;
        entry->func = (unsigned long)tp->rp.kp.addr;
        entry->ret_ip = (unsigned long)ri->ret_addr;
        for (i = 0; i < tp->nr_args; i++)
                entry->args[i] = call_fetch(&tp->args[i].fetch, regs);
-       perf_tp_event(call->id, entry->ret_ip, 1, entry, size);
-
-end:
-       perf_swevent_put_recursion_context(rctx);
-end_recursion:
-       local_irq_restore(irq_flags);
 
-       return 0;
+       perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1,
+                              irq_flags, regs);
 }
 
-static int probe_profile_enable(struct ftrace_event_call *call)
+static int probe_perf_enable(struct ftrace_event_call *call)
 {
        struct trace_probe *tp = (struct trace_probe *)call->data;
 
@@ -1379,7 +1287,7 @@ static int probe_profile_enable(struct ftrace_event_call *call)
                return enable_kprobe(&tp->rp.kp);
 }
 
-static void probe_profile_disable(struct ftrace_event_call *call)
+static void probe_perf_disable(struct ftrace_event_call *call)
 {
        struct trace_probe *tp = (struct trace_probe *)call->data;
 
@@ -1404,7 +1312,7 @@ int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
                kprobe_trace_func(kp, regs);
 #ifdef CONFIG_PERF_EVENTS
        if (tp->flags & TP_FLAG_PROFILE)
-               kprobe_profile_func(kp, regs);
+               kprobe_perf_func(kp, regs);
 #endif
        return 0;       /* We don't tweek kernel, so just return 0 */
 }
@@ -1418,7 +1326,7 @@ int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
                kretprobe_trace_func(ri, regs);
 #ifdef CONFIG_PERF_EVENTS
        if (tp->flags & TP_FLAG_PROFILE)
-               kretprobe_profile_func(ri, regs);
+               kretprobe_perf_func(ri, regs);
 #endif
        return 0;       /* We don't tweek kernel, so just return 0 */
 }
@@ -1432,30 +1340,33 @@ static int register_probe_event(struct trace_probe *tp)
        if (probe_is_return(tp)) {
                tp->event.trace = print_kretprobe_event;
                call->raw_init = probe_event_raw_init;
-               call->show_format = kretprobe_event_show_format;
                call->define_fields = kretprobe_event_define_fields;
        } else {
                tp->event.trace = print_kprobe_event;
                call->raw_init = probe_event_raw_init;
-               call->show_format = kprobe_event_show_format;
                call->define_fields = kprobe_event_define_fields;
        }
+       if (set_print_fmt(tp) < 0)
+               return -ENOMEM;
        call->event = &tp->event;
        call->id = register_ftrace_event(&tp->event);
-       if (!call->id)
+       if (!call->id) {
+               kfree(call->print_fmt);
                return -ENODEV;
+       }
        call->enabled = 0;
        call->regfunc = probe_event_enable;
        call->unregfunc = probe_event_disable;
 
 #ifdef CONFIG_PERF_EVENTS
-       call->profile_enable = probe_profile_enable;
-       call->profile_disable = probe_profile_disable;
+       call->perf_event_enable = probe_perf_enable;
+       call->perf_event_disable = probe_perf_disable;
 #endif
        call->data = tp;
        ret = trace_add_event_call(call);
        if (ret) {
                pr_info("Failed to register kprobe event: %s\n", call->name);
+               kfree(call->print_fmt);
                unregister_ftrace_event(&tp->event);
        }
        return ret;
@@ -1465,6 +1376,7 @@ static void unregister_probe_event(struct trace_probe *tp)
 {
        /* tp->event is unregistered in trace_remove_event_call() */
        trace_remove_event_call(&tp->call);
+       kfree(tp->call.print_fmt);
 }
 
 /* Make a debugfs interface for controling probe points */
@@ -1507,28 +1419,67 @@ static int kprobe_trace_selftest_target(int a1, int a2, int a3,
 
 static __init int kprobe_trace_self_tests_init(void)
 {
-       int ret;
+       int ret, warn = 0;
        int (*target)(int, int, int, int, int, int);
+       struct trace_probe *tp;
 
        target = kprobe_trace_selftest_target;
 
        pr_info("Testing kprobe tracing: ");
 
        ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target "
-                                 "$arg1 $arg2 $arg3 $arg4 $stack $stack0");
-       if (WARN_ON_ONCE(ret))
-               pr_warning("error enabling function entry\n");
+                                 "$stack $stack0 +0($stack)");
+       if (WARN_ON_ONCE(ret)) {
+               pr_warning("error on probing function entry.\n");
+               warn++;
+       } else {
+               /* Enable trace point */
+               tp = find_probe_event("testprobe", KPROBE_EVENT_SYSTEM);
+               if (WARN_ON_ONCE(tp == NULL)) {
+                       pr_warning("error on getting new probe.\n");
+                       warn++;
+               } else
+                       probe_event_enable(&tp->call);
+       }
 
        ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target "
                                  "$retval");
-       if (WARN_ON_ONCE(ret))
-               pr_warning("error enabling function return\n");
+       if (WARN_ON_ONCE(ret)) {
+               pr_warning("error on probing function return.\n");
+               warn++;
+       } else {
+               /* Enable trace point */
+               tp = find_probe_event("testprobe2", KPROBE_EVENT_SYSTEM);
+               if (WARN_ON_ONCE(tp == NULL)) {
+                       pr_warning("error on getting new probe.\n");
+                       warn++;
+               } else
+                       probe_event_enable(&tp->call);
+       }
+
+       if (warn)
+               goto end;
 
        ret = target(1, 2, 3, 4, 5, 6);
 
-       cleanup_all_probes();
+       ret = command_trace_probe("-:testprobe");
+       if (WARN_ON_ONCE(ret)) {
+               pr_warning("error on deleting a probe.\n");
+               warn++;
+       }
 
-       pr_cont("OK\n");
+       ret = command_trace_probe("-:testprobe2");
+       if (WARN_ON_ONCE(ret)) {
+               pr_warning("error on deleting a probe.\n");
+               warn++;
+       }
+
+end:
+       cleanup_all_probes();
+       if (warn)
+               pr_cont("NG: Some tests are failed. Please check them.\n");
+       else
+               pr_cont("OK\n");
        return 0;
 }